Simon 5 is coming soon!
Simon version 5 is currently in beta testing. It is a massive update, introducing a much-requested feature: syncing the Simon data between multiple Macs, plus a Simon Status service, a Link Checker filter, improved Find filter, iMessage and Speak Error notifiers, a new app icon, and much more.
Important: please note that Simon 5 requires a minimum of macOS 10.12 (Sierra), and will be a paid upgrade from Simon 4 after the beta. Purchasers since September 1, 2020 automatically get a version 5 license (that also works in previous versions).
Re: Replicate Simon to new hardware
Either approach would work, but probably easiest and best to install a fresh copy of the Simon app, in case your old copy isn't up-to-date. Re-licensing it is easy: just enter your name and email address in the license window, and click Find.
You should copy the data folder before launching Simon on the new machine, to avoid having to replace an empty data folder (and risk copying in the wrong direction!). If not, that's fine, just copy it when Simon isn't running.
You can copy the preferences file too, if desired (~/Library/Preferences/com.dejal.simon2.plist), though it's easy enough to set up the preferences again.
Let me know if you need any further help.